VEGA VEGASWING 75A - Manual (Page 3)

VEGASWING 71A and 75A 3
Product description
1 Product description
1.1 Function and configuration
VEGASWING series 70 vibrating level
switches detect levels of liquids with a vis-
cosity of 0.2 up to 10.000 mPa s and a den-
sity of
≥
0.6 g/cm 3 . Modular construction
enables their use in machines, plants, ves-
sels and pipelines, even in applications se-
verely limited in space. Typical applications
are overfill and dry run protection.
VEGASWING 71A is optionally available with
threads G 1 A and 1" NPT. The stainless steel
housing (1.4571) is in protection class IP 67.
VEGASWING 75A is mainly suitable for level
detection in the food processing and phar-
maceutical industry. Due to the polished
sensor surface (R
a
≤
0.5 µm or R
a
≤
1.5 µm)
bacteria have no chance to collect.
VEGASWING 75A is also suitable for CIP and
SIP cleaning. Many different hygienic fittings
such as conus with compression nut, Tri-
Clamp 1
1 /
2
" and 2", bolting, Tuchenhagen
Varivent or special hygienic connections are
available.
Due to the simple and rugged measuring
system, VEGASWING is virtually unaffected
by the chemical and physical properties of
the liquid. They work even under unfavour-
able conditions such as turbulences, air
bubbles, foam generation, buildup or varying
products. An adjustment to the medium is not
necessary.
The electronics can be exchanged without
problems. VEGASWING must not be re-
moved.
VEGASWING has an integrated test switch
which can be activated magnetically. It tests
the sensor electronics and the connected
instruments.
1.2 Principle of operation
The tuning fork is piezoelectrically energised
and vibrates at its mechanical resonance
frequency of approx. 400 Hz. This frequency
is transferred to the electronics of VEGAS-
WING. When the tuning fork is submerged in
the product, the frequency changes. This
change is detected by the integrated oscilla-
tor and converted into a switching command.
By changing of poles of the supply voltage,
the switching condition can be defined (max.
detection/min. detection). With the transistor
version, PNP or NPN action can be preset by
a different connection of the consumer (load).
The integrated fault monitoring detects:
- interruption of the connection cable to the
piezo elements
- extreme wear on the tuning fork
- break of the tuning fork
- no vibration.
If one of the stated failures is determined or in
case of voltage loss, the electronics takes on
a defined switching condition, e.g. the output
transistor blocks.